55785321 has 8 divisors (see below), whose sum is σ = 82644960. Its totient is φ = 37190196.

The previous prime is 55785253. The next prime is 55785377. The reversal of 55785321 is 12358755.

55785321 is a `hidden beast` number, since 55 + 78 + 532 + 1 = 666.

It is not a de Polignac number, because 55785321 - 2⁹ = 55784809 is a prime.

It is a super-2 number, since 2×55785321² = 6224004078146082, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (55784321) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1033035 + ... + 1033088.

It is an arithmetic number, because the mean of its divisors is an integer number (10330620).

Almost surely, 2^55785321 is an apocalyptic number.

It is an amenable number.

55785321 is a deficient number, since it is larger than the sum of its proper divisors (26859639).

55785321 is a wasteful number, since it uses less digits than its factorization.

55785321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2066132 (or 2066126 counting only the distinct ones).

The product of its digits is 42000, while the sum is 36.

The square root of 55785321 is about 7468.9571561229. The cubic root of 55785321 is about 382.0967222162.

The spelling of 55785321 in words is "fifty-five million, seven hundred eighty-five thousand, three hundred twenty-one".